Many mechanical assemblies comprise an arrangement wherein a rounded shaft is jam fitted with a component such as a bearing, impeller, gear, wheel or the like, which is mounted to rotate with the shaft. Similarly, many mechanical assemblies comprise arrangements wherein a component such as a bearing, race, seal or the like is jam fitted around its periphery to an opening in a housing, usually to encircle a shaft or the like extending through the opening of the housing. Typically the removal of such components from a shaft and/or housing for repair or replacement is problematic and requires use of a puller or the like tool.
For example, liquid cooled internal combustion engines are commonly designed to incorporate water pumps as an integral part of the engine and/or drive train. Particularly in marine engine embodiments, the water pump generally comprises a flexible impeller of varying size, dimensions and number of blades. The impeller generally comprises a plurality of slightly resilient curved arms arranged as spokes around a metal hub, the hub having a central opening for mounting to a shaft which rotates the impeller.
It is not unusual for such impellers to be removed for replacement and/or repair, with removal being generally time consuming because of the close tolerance positioning of the water pump on the motor, the positioning of the motor in the vehicle and/or boat, the jam fit by which the hub of the impeller is typically mounted to a water pump shaft and/or the effects of corrosion, dirt and the like among the shaft and the impeller. It is not unusual for a technician to be forced to use a pair of flat screw drivers to slowly pry the impeller from the shaft, creating the danger of damage to the housing and in many instances so damaging the impeller and/or housing as to make it non-repairable, non-rebuildable or even nonreusable once removed.
Similarly, many motors and/or machines generally comprise a rotatable shaft extending through an opening in a housing, with the housing comprising a bearing and/or seal which is jam fitted therein, the bearing or seal generally has a peripheral rigid collar for jammed retention to the housing and an interior facing elastomeric and/or machined surface for engaging the shaft and preventing leakage of fluids. When such seals or bearings need replacement it is not unusual for a technician to be forced to use a hammer and chisel or the like tools to force the seal or bearing from its fitted position, usually at the risk of damaging the component and/or the housing.
Various pullers have been proposed for use in removal of components from their supporting shaft but each have limitations in use. U.S. Pat. No. 5,341,553 discloses puller particularly suitable for pulling impellers from water pumps of marine engines, which purports to solve the problem of flexible impeller removal from water pump shafts, but has been found problematic in that it is easily misaligned and can cause damage to the impeller and even further jam the impeller on the shaft and make the removal process more difficult and even technically illusive to a technician.
It is a primary object of the present invention to provide an improved puller which will facilitate the removal of components from shafts and housings.
It is a further object of the invention to improve the impeller puller of U.S. Pat. No. 5,341,553 to resolve the difficulty encountered with misalignment during removal of flexible impellers and make it adaptable to pulling seals or the like.
It is another object of the invention to provide a universal puller which is more easily aligned and more certain in operation for the effective removal of a flexible impeller with minimal damage to the impeller.
It is still another object of the invention to provide an improved puller which can be conveniently adapted for pulling components from a shaft and/or from a housing surrounding an opening.
These and other objects of the invention will become apparent in the following recitation of the invention.